What is the purpose of a fuse in an electrical circuit?

A fuse serves the essential purpose of protecting an electrical circuit by interrupting the flow of electricity in the event of an overload. When the current flowing through the circuit exceeds a certain threshold, the fuse will blow or melt, creating an open circuit. This interruption prevents further current flow, which could otherwise lead to overheating, component damage, or even fire.

The other options describe functions that are not typically managed directly by a fuse. While preventing power supply ripple and limiting current are important considerations in circuit design and can impact safety and functionality, they are managed through different components like capacitors and resistors, respectively. A fuse's primary role is to safeguard the circuit from excessive current, making option B the most accurate description of its purpose.